This invention relates to a computer network, and more particularly, to a technology for synchronizing a time of a device on a network
One technology of synchronizing a device on a computer network is a method of using communication with a reference clock. Particularly, it is required for the time synchronization to be applied widely, to enable highly accurate synchronization, and to be inexpensive, and new methods have been standardized to satisfy these requirements. One representative standard thereof is IEEE 1588 version 2, Precision Time Protocol (hereinafter, referred to as IEEE 1588 v2).
According to IEEE 1588 v2, time synchronization is performed by measuring a delay on a communication path based on a difference in timestamp during communication, receiving a packet for notifying a time for synchronization, and considering the delay for the received time synchronization packet. According to IEEE 1588 v2, all network devices synchronize a time referring to one grandmaster clock provided on a network. On this occasion, a node having the highest clock accuracy is automatically selected as the grandmaster clock according to a protocol of IEEE 1588 v2.
Moreover, JP 2009-65579 A1 describes a method of synchronizing a time while considering paths on a network.